Adapter for fiberglass tool handles and other fiberglass connections

ABSTRACT

An adapter for connecting tool heads to fiberglass tool handles and for making other fiberglass attachments. An adapter which is preferably formed in two sections is mounted around and over the end of the tool handle. Interlocking means or frictional engagement are provided to hold the adapter in place. The upper portions of the exterior walls of the adapter sections are tapered complementarily to the inwardly tapered upper section of a conventional double tapered tool head opening and are adapted to make frictional engagement therewith. The adapter is capable of being cold molded to a limited degree to make a locking engagement with the tool head adjacent to the midportion of the tool head opening. A plurality of spacers are removably mounted in the adapter sections to compensate for variations in the tool head opening. Molded inserts are also provided so that a single adapter can be used on two different standard sizes of tool handles.

Carmien 1.1] 3,819,288 June 25, 1974 ADAPTERFOR FIBERGLASS TOOL HANDLESAND OTHER IBERGLASS CONNECTIONS Inventor: Joseph Allen Cat-mien, SunValley,

Calif.

Assignee: Nupla Corporation, Sun Valley,

Calif.

Filed: Jan. 2, 1973 App]. No.: 320,554

Related U.S. Application Data Continuation-impart of Ser. No. 221,615,Jan. 28, 1972, Pat. No. 3,753,602.

U.S. Cl 403/247, 403/263, 403/369 Int. CL; B25g 3/24 8] Field of Search403/247,.249, 250', 253, 403/254, 256, 257, 261, 26-3, 344, 369, 372,

References Cited UNITED STATES PATENTS 3/1882 Hardie 403/369- 6/1933Cochrane 403/334-j 4/l950 Slayton, Jr. 403/247 X lZa 1 2,755,112 7/1956Klancnik 403/263 X 'Primary Examiner-Werner H. Schroeder Attorney,Agent, or Firm-Robert C. Comstock 5 7] ABSTRACT An adapter forconnecting tool heads to fiberglass tool handles and for making otherfiberglass attachments. An adapter which is preferably formed in twosections is mounted around and over the end of the tool handle.Interlocking means or frictional engagement are provided to hold theadapter in place. The upper portions of the exterior walls of theadapter sections are tapered complementarily to the inwardly taperedupper section of a conventional double tapered tool head opening and areadapted to make frictional engagement therewith. The adapter is capableof being cold molded to a limited degree to make a locking engagementwith the tool head adjacent to the midportion of the tool head opening.A plurality of spacers are removably mounted in the adapter sections tocompensate for variations in the tool head opening. Molded inserts arealso provided so that a single adapter can be used on two differentstandard sizes of tool handles.

10 Claims, 8 Drawing Figures /3a V A l g ADAPTER FOR FIBERGLASS TOOLHANDLES AND OTHER FIBERGLASS CONNECTIONS REFERENCES TO RELATEDAPPLICATION BACKGROUND OF THE INVENTION 1. Field of the Invention Theinvention relates to an adapter for fiberglass tool handles such ashammers, sledges, axes, etc. which may also be used for otherattachments or connections to fiberglass such as guy rods, catenaries,concrete reinforcing bars and any other uses where a connection is madeto a fiberglass rod or bar.

2. Description of the Prior Art Until recent years, the only materialused for handles in striking, cutting and/or prying tools such ashammers, sledges, peaveys, axes, etc. has been wood. For this reason,the method of attaching the handle to the head, whatever type it mighthave been, was dictated by the property characteristics of the material,namely wood.

On many tools other than picks and mattocks, the eyehole has a doubletaper or venturi shape, elliptical and conical, with the smallest crosssection disposed at approximately the midpoint of the head. The upperconical section, which received the portion of the head farthest awayfrom the grip, is for the purpose of allowing the wood to be expanded bymeans of a wedge, so that the wood is larger than the waist of theeyehole and the head cannot come off the wood handle when used.

The taper starting at the bottom, or the side into which the handle isnormally inserted, is for the purpose of accommodating variations in theoriginal wood handle size and the eyehole of the head and, moreimportantly, allowing the user to re-tighten the head when it becomesloose by driving the handle further into the head and then driving theoriginal wedge further in or adding another wedge. v

An ideal tool handle is one which is formed of fiberglass rather thanwood. Fiberglass is far stronger and far outlasts wood. Tool headscannot be attached to fiberglass handles in the same manner in whichthey are attached to wood handles because, for example, a wedge cannotbe driven into the end of a fiberglass handle in order to spread it inthe manner conventionally used with a wood handle.

In this connection, it must be realized that most striking, pryingand/or cutting tools are not precision made and, therefore, the eyeholehas a rather liberal tolerance as to its size and shape.

Inasmuch as this invention contemplates a handle assembled to a head asa new product, and also a handle used as a replacement, the attachmentmethod must accommodate thesevarying conditions.

SUMMARY OF THE INVENTION double tapered tool head opening, regardless ofwhatever variations may exist in the dimensions, tolerances and surfaceimperfections of the tool head opening.

Another object of the invention is to provide such an adapter which iscapable of being used with two different standard sizes of tool handlesand handle receiving openings.

The invention utilizes an adapter which is preferably divided into twosections. The interior of the adapter and the exterior of the handle areprovided with mating means such as complementary notches and projectionswhich prevent longitudinally axial movement of the adapter with respectto the tool handle.

Each of the adapter'sections has a closed top or end portion adjacent towhich the exterior walls of the adapter sections are tapered outwardlyin an amount somewhat greater than the inwardly directed taper of theupper portion of the tool head opening. The portion of the exteriorwalls of the adapter sections adjacent thereto is taperedcomplementarily to the tapering of the upper portion of the tool headopening and is adapted to form a frictional engagement therewith.

The head of the tool is first mounted on the handle. The adaptersectionsare then positioned surrounding the handle and in engagement therewith.The head of the tool is then slid along the handle into a position whereits opening surrounds the adapterQThe head is then firmly driven ontothe adapter until the upper portion of the adapter is firmly wedgedwithin the upper tapered portion of the tool head opening.

In order to compensate for variations in the dimensions, tolerances andsurface inperfections of various tool head openings, each of the adaptersections is preferably furnished to the user with three spacersremovably mounted therein. The spacers are removed as required toprovide a perfect fit between the adapter and tool head.

Since most tool heads are of two standard sizes which vary only inwidth, a pair of molded inserts are provided which permit the adapter tobe used with either size of handle.

It is accordingly among the objects of the invention to provide anadapter for fiberglass tool handles which is capable of being used withsubstantially any tool head now in use or manufactured within the lasttwenty-five years. A more particular object of the invention is toprovide such an adapter which utilizes removably mounted spacers whichcompensate for variations'iri dimensions and irregularities in varioustool head openings.

Another object of the invention is to provide such an adapter which iscapable of being used with two different standard sizes of tool handles.

A further object of the invention is to provide a tool handle mountingmeans which not only satisfies but actually far exceeds the'safetypull-off standards specified by the federal government.

It is accordingly among the objects of the invention to provide anadapter having all of the advantages and benefits of the structure setforth and described in further detail hereinafter in this specification.

The invention also comprises such other objects, advantages andcapabilities as will later more fully appear and which are inherentlypossessed by the invention.

While there is shown in the accompanying drawings a preferred embodimentof the invention, it should be understood that the same is susceptibleof modification 3 and change without departing from the spirit of theinvention.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of a toolwith the adapter in use thereon;

FIG. 2 is a longitudinal sectional view of the adapter portion of thetool shown in FIG. 1, with two spacers in each adapter section;

FIG. 3 is a transverse sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is an enlarged partial sectional view similar to FIG. 2 showingthe locking relationship between the adapter and tool head;

FIG. 5 is an exploded isometric view showing the spacer and the interiorof an adapter section;

FIG. 6 is an isometric view of the exterior of the handle, showing thenotch which receives the projections on the interior of the adaptersections;

FIG. 7 is an isometric view of an insert used for fitting a differentsize handle;

FIG. 8 is a transverse sectional view of an adapter section with aninsert mounted therein and a spacer shown in phantom lines.

DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment which hasbeen selected to illustrate the invention comprises a fiberglasselongated member 10. The elongated member 10 may comprise the handle ofa tool or a rod or other member to which a connection or attachment isto be made. The elongated member 10 customarily has flat sides androunded edges. The end of the elongated member 10 to which theattachment is to be made may be provided with a pair of oppositelydisposed indentations 11.

A pair of identially formed hemispherical crosssection adapter sections12 and 13 are provided with vertically straight rounded interiorsurfaces which conform generally to and are complementary with theexterior of the rounded edges of the elongated member 10. Each of theadapter sections 12 and 13 is provided on its interior with a pair ofoppositely disposed projections 14 and 15 respectively which conformgenerally to and are complementary with the configuration of theindentations 11 in the end of the elongated member 10.

The outer walls of the adapter sections 12 and 13 are tapered outwardlyalong a short portion 12b and 13b respectively at their upper endssomewhat in excessof 4, which is the normal taper of a tool headopening. A short circumferential ridge 18 protrudes outwardly from theouter wall of each of the adapter sections in approximate alignment withthe bottom of the top walls 12a and 13a.

Beneath the ridge 18, slightly less tapered portions 120 and 13c extendat approximately a 4 angle to adjacent the bottom of the projections 14and 15. The remaining lower portions 12d and 13d of the outer walls aresubstantially straight.

If the elongated member 10 comprises the handle of a tool, it ispreferable for the ends of the adapter sections to extend longitudinallyalong the sides of the handle. In this way, any striking or prying forceresulting from the use of the tool will not be directed in such a mannerthat it will tend to separate the adapter sections. In such case, whichis illustrated in the drawings herein, each of the projections 14 and 15extends approximately half way across each of the indentations l l.

The tool or the like to which attachment is to be made comprises a head16 having extending therethrough a double tapered opening 17 comprisingan inwardly directed tapered portion 17a at the top, an outwardlydirected tapered portion 17b at the bottom and a straight midportion 17ctherebetween.

A double tapered tool head opening should in theory comprise a pair ofconical tapered portions directed inwardly from the top and bottom ofthe tool head and meeting at a point in the center. In actual practice,the cutting tools which form these openings do not quite reach thecenter. This leaves a wafer at the center which is punched out, leavinga straight side wall portion 170, between the inner ends of the twotapered side wall portions 17a and 17b. As the cutting tools becomeprogressively worn, the thickness of the wafer and the center straightportion 17c increases. In the average tool head opening, there isaccordingly a straight side wall portion 17c of varying length disposedat the center between the two tapered side wall portions 17a and 17b.

The adapter sections 12 and 13 are preferably formed of material whichis capable of being cold molded to a limited degree under pressure sothat they will make a secure locking engagement with the tool head 16 inthe manner described hereinafter and will also compensate for minorsurface irregularities and tolerance variations in the head 16 and/orhandle 10. The adapter material should also preferably have a highcoefficient of friction, so that it forms a relatively high degree offrictional engagement with both the tool handle and head. At the presenttime, glass filled nylon has been found to be the most satisfactorymaterial for use in forming the adapter. It has the properties set forthabove, plus the strength and other properties required for the adapter.Polyurethane, polycarbonate, acrylonitrile butadiene styrene and similarmoldable thermoplastic materials may also be used.

Removably mounted within each of the adapter sections 12 and 13 asfurnished to the user are three overlying spacers 20. The spacers 20 arepreferably approximately ten thousandths of an inch thick. The spacers20 may be formed of any suitable material, but fiber has been foundparticularly satisfactory in use. Other materials such as vinyl,fiberglass or phenolic sheet, insulating type fish paper or othercomparable material may also be used.

The spacers 20 are formed from sheet material which is normally flat.When they are curved to fit within the interior of the adapter sections12 and 13, they try to return to a flat configuration and their sideedges are accordingly resiliently urged into frictional engagement withthe inner side walls of the adapter sections. The spacers 20 are alsoprovided with notches 21 in their side edges which are formedcomplementarily to and are fitted around the projections 14 and 15. Theupper ends of the spacers 20 are accordingly quite securely held betweenthe end walls 12a and 13a and the projections 14 and 15 in addition tothe side edge frictional engagement described above.

The spacers 20 are preferably of progressively increasing length so thattheir lower ends are shingled with the longest on top, to permit them tobe manually engaged one at a time for the purpose of removing thespacers from the adapter sections.

The spacers 20 are used tocontrolthe longitudinal positioning of theadapter sections 12 and 13 within the tool head 16. It has been foundthat the manufacturers of forged tool heads have not consistentlymaintained high standards of accuracy with regard to dimensions andtolerances of the tool head openings 17. As a result, the presentinvention cannot be utilized in a universal manner with all tool headsunless some means is provided which will compensate for the variationswhich exist and which cannot be changed. The adapter sections 12 and 13are accordingly furnished to the user with three spacers 20 mountedwithin each adapter section. v

In order to mount the head 16, it is first slid over the end of theelongated member which carried the indentationsll. The two adaptersections 12 and 13 are then mounted on the end of the elongated member10 in such a position that their projections 14 and 15 fit into andengage the indentations 11. The head 16 is then moved back along theelongated member until the inwardly tapered portion 17a of the opening17 makes substantial frictional engagement with the outer walls of theadapter sections 12 and 13.

Further movement of the head 16 toovercome such frictional resistancemay be achieved either by suitable mechanical means or by moving-theelongated member vertically and striking the outer ends 12a and 13a ofthe adapter sections upon the ground or upon any firm surface so thatthe weight of the head 16 acts to drive it downwardly into tighterfrictional engagement with the outer walls of the adapter sections 12and 13. If there is a perfect fit, this action is continued untilsubstantially the entire length of the 4 taper outer wall portions 12cand 130 of the adapter sections are in frictional engagement with thecomplementary 4 inwardly tapering portions 17a of the opening 17 in thetool head 16. When this occurs, the upper end'of the tool head 16 shouldbe in substantial alignment with the ridges 18 on the outer walls of theadapter sections 12 and 13. It is important to note that as the toolhead 16 is driven into engagement with the adapter sections 12 and 13,the outer walls of the adapter sections adjacent to the lower ends ofthe tapered portions 12c and 130 are severly compressed inwardly as theyare driven through the straight midportion 17c of the opening 17.

Once they pass through the straight midportion 170,

they move radially outwardly by their own resilience to engage the upperpart of the bottom inwardly tapered portion 17b of opening 17.

The outer walls of the adapter sections 12 and 13 accordingly take-on toa limited degree an hourglass or double tapered configuration comparableto that of the opening 17. This is best shown in FIGS. 2 and 4 of thedrawings, in which it will be seen that the portions of the walls andwhich are directly beneath or inwardly from the midportion of the toolhead opening 17 are slightly wider than the midportion 17c and they forma locking engagement which, along with the frictional engagement aboveit, resists removal of the tool head 16. I

This compression and expansion of the adapter sections 12 and 13 may becompared to cold molding in that the material forming the adaptersections is caused to cold flow and become molded into a lockingconfiguration.

If the tool head 16 cannot be driven to the point where its upper edgeis aligned with the ridges 18, the tool head is removed and one or moreof the spacers 20 removed from either or both of the adapter sections 12and 13. Each spacer 20 which is removed will provide approximately 6inch additional longitudinal movement of the tool head 16 with respectto the adapter sections 12 and 13. It is accordingly possible to obtainprecisely the proper positioning of the tool head 16 on the handle 10regardless of the particular dimensions of the opening 17 throughremoval of the proper number of spacers 20.

The spacers 20 accordingly make the adapter truly universal so that itcan be used in almost any tool head opening regardless of the amount ofinperfections and variations in dimensions and tolerances.

Most of the tool handles (and tool head openings for receiving them)which are presently in use are 1 inch wide in their smaller transversedimension, but may be either 1% inches or 1% inches in their longertransverse dimension. In order that the adapter of the present inventionmay be used with both sizes of handles, a pair of removable inserts 40is provided. The insert 40 is shown in FIG. 7 of the drawings and isalso shown in use within an adapter section in FIG. 8.

The inserts 40 are preferably molded from the same material as theadapter sections 12 and 13, such as glass filled nylon or other moldablethermoplastic material. The insert 40 is substantially rigid and onlyslightly resilient, as opposed to the easy flexibility of the spacers20. The insert 40 is formed in an arcuate configuration and has acrescent-shaped cross section, as best shown in FIG. 8. Its curvature iscomplementary to that of the inside of the adapter section and it is soconstructed as to be easily but securely snap fit therein.

The midportion of the insert 40 has a thickness of approximately 62/1000 inch, so that an insert 40 mounted in each of the adapter sections12 and 13 effectively reduces the combined inner dimensions of theadapter sections by approximately A; inch. The inserts 40 accordinglypermit use of the same adapter on a 1% inches handles with the inserts40 and a 1% inches handle without the inserts.

The inserts 40 may be used along with the spacers 20, which arepreferably mounted above the inserts 40.

The extreme flared portions 12b and 13b at the upper end of the adaptersections 12 and 13 act as an added safety feature to prevent the toolhead 16 from accidentally coming off the end of the adapter.

I claim:

1. An adapter for connecting a tool head to a fiberglass tool handle andfor making other attachments to fiberglass members in which a tool heador other member being attached has a double tapered opening with conicalside walls tapering inwardly from the top and bottom thereof joined atthe center by a short portion having substantially straight side walls,said adapter comprising a plurality of sections having a combinedoutwardly tapered exterior formed substantially complementarily to theupper tapered portion of said tool head opening and adapted to fittherein, said adapter being mounted on the end of said handle so thatthe end of said handle is substantially completely surroundedcircumferentially by said adapter, engagement means between said adapterand tool handle for preventing substantial longitudinal movement of saidadapter with respect to said handle, said tool head adapted to bebrought into tighter engagement with said adapter by the application offorce to the end of said tool handle, said adapter being formed ofmaterial which is solid but somewhat malleable, so as to becapable ofbeing cold molded in response to pressure exerted thereon in mountingsaid tool handle on said adapter so that the exterior of said adapter iscompressed inwardly as it is driven through the straight portion of saidopening and then moves radially outwardly by its own resilience toengage the lower edge of the straight portion of said opening and form alocking engagement therewith which prevents undesirable longitudinalmovement of said tool head with respect to said adapter, the exterior ofsaid adapter also extending into surface irregularities and dimensionalvariations in the upper and midportion of said opening.

2. The structure described in claim 1, and at least one spacer removablymounted in each of said adapter sections, whereby said adapter can beused in tool head openings of various dimensions.

3. The structure described in claim 2, said spacers being held withinsaid adapter sections by snap fit engagement resulting from bending flatsheet material to an arcuate configuration 4. The structure described inclaim 3, there being a pair of said adapter sections having three ofsaid spacers removably mounted in overlying relationship to each otherwithin each of said sections.

5. The structure described in claim 4, each of said spacers having athickness of approximately 10/1000 of an inch, whereby said spacersprovide variability between two difierent standard sizes of tool headopenmgs.

6. The structure described in claim 5, the lower ends of said spacersbeing shingled to facilitate manual removal of said spacers from saidadapter sections.

7. The structure described in claim 1, there being a pair of saidadapter sections, and a molded substantially rigid arcuate insertremovably mounted within each of said adapter sections, said insertsbeing of sufficient thickness to permit the use of said adapter onhandles of two different standard widths.

8. The structure described in claim 7, said inserts being held withinsaid adapter sections by frictional engagement of their side edges withthe interior of said adapter sections.

9. The structure described in claim 7, and at least one spacer mountedwithin each of said adapter sections in overlying relationship to saidinserts.

10. The structure described in claim 9, there being three of saidspacers mounted within each of said adapter sections in overlyingrelationship to said inserts, said spacers being held in place by snapfit engagement resulting from bending flat sheet material to an arcuateconfiguration.

1. An adapter for connecting a tool head to a fiberglass tool handle andfor making other attachments to fiberglass members in which a tool heador other member being attached has a double tapered opening with conicalside walls tapering inwardly from the top and bottom thereof joined atthe center by a short portion having substantially straight side walls,said adapter comprising a plurality of sections having a combinedoutwardly tapered exterior formed substantially complementarily to theupper tapered portion of said tool head opening and adapted to fittherein, said adapter being mounted on the end of said handle so thatthe end of said handle is substantially completely surroundedcircumferentially by said adapter, engagement means between said adapterand tool handle for preventing substantial longitudinal movement of saidadapter with respect to said handle, said tool head adapted to bebrought into tighter engagement with said adapter by the application offorce to the end of said tool handle, said adapter being formed ofmaterial which is solid but somewhat malleable, so as to be capable ofbeing cold molded in response to pressure exerted thereon in mountingsaid tool handle on said adapter so that the exterior of said adapter iscompressed inwardly as it is driven through the straight portion of saidopening and then moves radially outwardly by its own resilience toengage the lower edge of the straight portion of said opening and form alocking engagement therewith which prevents undesirable longitudinalmovement of said tool head with respect to said adapter, the exterior ofsaid adapter also extending into surface irregularities and dimensionalvariations in the upper and midportion of said opening.
 2. The structuredescribed in claim 1, and at least one spacer removably mounted in eachof said adapter sections, whereby said adapter can be used in tool headopenings of various dimensions.
 3. The structure described in claim 2,said spacers being held within said adapter sections by snap fitengagement resulting from bending flat sheet material to an arcuateconfiguration.
 4. The structure described in claim 3, there being a pairof said adapter sections having three of said spacers removably mountedin overlying relationship to each other within each of said sections. 5.The structure described in claim 4, each of said spacers having athickness of approximately 10/1000 of an inch, whereby said spacersprovide variability between two different standard sizes of tool headopenings.
 6. The structure described in claim 5, the lower ends of saidspacers being shingled to facilitate manual removal of said spacers fromsaid adapter sections.
 7. The structure described in claim 1, therebeing a pair of said adapter sections, and a molded substantially rigidarcuate insert removably mounted within each of said adapter sections,said inserts being of sufficient thickness to permit the use of saidadapter on handles of two different standard widths.
 8. The structuredescribed in claim 7, said inserts being held within said adaptersections by frictionAl engagement of their side edges with the interiorof said adapter sections.
 9. The structure described in claim 7, and atleast one spacer mounted within each of said adapter sections inoverlying relationship to said inserts.
 10. The structure described inclaim 9, there being three of said spacers mounted within each of saidadapter sections in overlying relationship to said inserts, said spacersbeing held in place by snap fit engagement resulting from bending flatsheet material to an arcuate configuration.